Collaborative Research: Cognitive Overload versus Enhanced Performance: Is more information always better?

University Of Texas At Austin, Austin TX

Investigators

Abstract

As anyone who has seen the display of a peacock can attest, communication signals form some of the most striking features of animal diversity on our planet. A fundamental question to be answered is, under what conditions do elaborate communication signals develop? To address this, a series of experiments will be conducted on two inhabitants of the Central American rainforest, the tungara frog, and its predator, the frog-eating bat. Male tungara frogs vocalize in the noisy backdrop of the rainforest as they attempt to attract a mate. While vocalizing, the frogs also inflate a large sac in their throat which generates a cascade of water ripples surrounding them. The experiments will address how and when each of these different signal components is used by a female frog searching for a mate or a bat searching for a meal. A common assumption in studies of animal behavior is that, additional information in an animal's signal always improves the ability of signal recipients to locate that signaler. In studies on humans, however, it is understood that more information can lead to cognitive overload and degrade decision performance. This study will address the conditions under which added information improves or degrades the efficiency of animal communication signals. The project will also incorporate training of future scientists, ranging from undergraduate students to post-doctoral researchers. Further, the knowledge gained from the project will be disseminated through student training at universities and primary schools as well as public outreach through museum displays. A fundamental question in animal behavior is, how do animals utilize available information to inform adaptive behaviors? In behavioral ecology there is often the implicit assumption that more information is better. In human psychophysics, however, there is substantial evidence to show that more information can lead to cognitive overload and disrupt signal detection and decision-making. Previous results from the investigators have made it clear that information in the male tungara frog's mating display is not linearly related to the response of two receivers, the female frog or its predator, the frog-eating bat. To address the question, "is more information always better," a series of playback experiments will be conducted under conditions of increasingly complex multimodal background noise. These experimental noise levels will mimic the variable noise levels that occur naturally in the environment. The performance (decision accuracy and latency) of the two receivers (female frog and bat predator) to playback calls will be assessed, making a critical contribution to an understanding of how animal decision-making occurs in a complex world. This will be the first study to explicitly contrast hypotheses that added information in the environment leads to either enhanced performance or cognitive overload on the part of the receiver. An added value of this study is that it will yield information on two very different species, with fundamentally different sensory systems and cognitive abilities. This will enhance the generality of the interpretations, providing insights into how different cognitive systems deal with environmental noise. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.